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Braune M, Metelmann M, de Fallois J, Pfrepper C, Barrantes-Freer A, Hiller GGR, Unger S, Seelow E, Halbritter J, Pelz JO. Imbalance of the von Willebrand Factor - ADAMTS-13 axis in patients with retinal vasculopathy with cerebral leukoencephalopathy and systemic manifestations (RVCL-S). Neurol Res Pract 2024; 6:32. [PMID: 38898536 PMCID: PMC11188181 DOI: 10.1186/s42466-024-00327-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Accepted: 05/08/2024] [Indexed: 06/21/2024] Open
Abstract
BACKGROUND Retinal vasculopathy with cerebral leukoencephalopathy and systemic manifestations (RVCL-S) is an ultra-rare, autosomal-dominant small vessel disease caused by loss-of-function variants in the gene TREX1. Recently, elevated serum levels of von Willebrand Factor Antigen (vWF-Ag) pointed to an underlying endotheliopathy, and microvascular ischemia was suggested to contribute to the neurodegeneration in RVCL-S. Aim of this study was to further elucidate the endotheliopathy in RVCL-S. METHODS vWF-Ag and ADAMTS-13 activity were repeatedly measured in two patients with genetically confirmed RVCL-S. Renal biopsy of both RVCL-S patients and autoptic brain, renal, hepatic, and pulmonary specimen of one patient with RVCL-S were examined immunohistochemically in comparison to matched controls. In addition, cerebral methylome analysis was performed in the autoptic brain specimen calculating differentially methylated positions compared to controls. RESULTS While vWF-Ag and activity was strongly elevated, ADAMTS-13 activity was low in RVCL-S and further decreased over the course of the disease. Autoptic brain specimen showed signs of thromboinflammation in cerebral small vessels, and vWF-Ag staining was strongly positive in cerebral and renal small vessels in RVCL-S, while only a light to moderate vWF-Ag staining was found in controls. Cerebral methylome analysis yielded 115 differentially methylated CpGs (p < 0.05) in the deceased RVCL-S patient compared to the eight controls without brain pathology. One of the hypomethylated genes coded for ADAMTS-13 (p = 0.00056). CONCLUSIONS These findings point to an imbalance of the vWF - ADAMTS-13 axis in patients with RVCL-S, that may finally lead to an accumulation of vWF-Ag in renal and cerebral small vessels. Elevated vWF-Ag levels may serve as an early serum marker reflecting disease activity. If confirmed, therapeutic approaches might aim at an inhibition of vWF-Ag or increase of ADAMTS-13 activity in the future.
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Affiliation(s)
- Max Braune
- Paul-Flechsig-Institute for Neuropathology, University Hospital Leipzig, Leipzig, Germany
| | - Moritz Metelmann
- Department of Neurology, University Hospital Leipzig, Liebigstraße 20, Leipzig, 04103, Germany
| | | | - Christian Pfrepper
- Division of Haemostaseology, Medical Department I, University Hospital Leipzig, Leipzig, Germany
| | - Alonso Barrantes-Freer
- Paul-Flechsig-Institute for Neuropathology, University Hospital Leipzig, Leipzig, Germany
| | | | - Susette Unger
- Division of Rheumatology, Hospital St. Georg, Leipzig, Germany
| | - Evelyn Seelow
- Department of Nephrology and Medical Intensive Care, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Jan Halbritter
- Division of Nephrology, University Hospital Leipzig, Leipzig, Germany.
- Department of Nephrology and Medical Intensive Care, Charité Universitätsmedizin Berlin, Berlin, Germany.
| | - Johann Otto Pelz
- Department of Neurology, University Hospital Leipzig, Liebigstraße 20, Leipzig, 04103, Germany.
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2
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Capdeville N, Schindele P, Puchta H. Increasing deletion sizes and the efficiency of CRISPR/Cas9-mediated mutagenesis by SunTag-mediated TREX1 recruitment. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 118:277-287. [PMID: 38113345 DOI: 10.1111/tpj.16586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 11/27/2023] [Accepted: 11/30/2023] [Indexed: 12/21/2023]
Abstract
Previously, it has been shown that mutagenesis frequencies can be improved by directly fusing the human exonuclease TREX2 to Cas9, resulting in a strong increase in the frequency of smaller deletions at the cut site. Here, we demonstrate that, by using the SunTag system for recruitment of TREX2, the mutagenesis efficiency can be doubled in comparison to the direct fusion in Arabidopsis thaliana. Therefore, we also tested the efficiency of the system for targeted deletion formation by recruiting two other 3'-5' exonucleases, namely the human TREX1 and E. coli ExoI. It turns out that SunTag-mediated recruitment of TREX1 not only improved the general mutation induction efficiency slightly in comparison to TREX2, but that, more importantly, the mean size of the induced deletions was also enhanced, mainly via an increase of deletions of 25 bp or more. EcExoI also yielded a higher amount of larger deletions. However, only in the case of TREX1 and TREX2, the effect was predominately SunTag-dependent, indicating efficient target-specific recruitment. Using SunTag-mediated TREX1 recruitment at other genomic sites, we were able to obtain similar deletion patterns. Thus, we were able to develop an attractive novel editing tool that is especially useful for obtaining deletions in the range from 20 to 40 bp around the cut site. Such sizes are often required for the manipulation of cis-regulatory elements. This feature is closing an existing gap as previous approaches, based on single nucleases or paired nickases or nucleases, resulted in either shorter or longer deletions, respectively.
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Affiliation(s)
- Niklas Capdeville
- Department of Molecular Biology, Karlsruhe Institute of Technology (KIT), Joseph Gottlieb Kölreuter Institute for Plant Sciences, Fritz-Haber-Weg 4, 76131, Karlsruhe, Germany
| | - Patrick Schindele
- Department of Molecular Biology, Karlsruhe Institute of Technology (KIT), Joseph Gottlieb Kölreuter Institute for Plant Sciences, Fritz-Haber-Weg 4, 76131, Karlsruhe, Germany
| | - Holger Puchta
- Department of Molecular Biology, Karlsruhe Institute of Technology (KIT), Joseph Gottlieb Kölreuter Institute for Plant Sciences, Fritz-Haber-Weg 4, 76131, Karlsruhe, Germany
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3
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Mecca M, Picerno S, Cortellino S. The Killer's Web: Interconnection between Inflammation, Epigenetics and Nutrition in Cancer. Int J Mol Sci 2024; 25:2750. [PMID: 38473997 DOI: 10.3390/ijms25052750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 02/21/2024] [Accepted: 02/23/2024] [Indexed: 03/14/2024] Open
Abstract
Inflammation is a key contributor to both the initiation and progression of tumors, and it can be triggered by genetic instability within tumors, as well as by lifestyle and dietary factors. The inflammatory response plays a critical role in the genetic and epigenetic reprogramming of tumor cells, as well as in the cells that comprise the tumor microenvironment. Cells in the microenvironment acquire a phenotype that promotes immune evasion, progression, and metastasis. We will review the mechanisms and pathways involved in the interaction between tumors, inflammation, and nutrition, the limitations of current therapies, and discuss potential future therapeutic approaches.
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Affiliation(s)
- Marisabel Mecca
- Laboratory of Preclinical and Translational Research, Centro di Riferimento Oncologico della Basilicata (IRCCS-CROB), 85028 Rionero in Vulture, PZ, Italy
| | - Simona Picerno
- Laboratory of Preclinical and Translational Research, Centro di Riferimento Oncologico della Basilicata (IRCCS-CROB), 85028 Rionero in Vulture, PZ, Italy
| | - Salvatore Cortellino
- Laboratory of Preclinical and Translational Research, Responsible Research Hospital, 86100 Campobasso, CB, Italy
- Scuola Superiore Meridionale (SSM), Clinical and Translational Oncology, 80138 Naples, NA, Italy
- S.H.R.O. Italia Foundation ETS, 10060 Candiolo, TO, Italy
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4
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Mathavarajah S, Vergunst KL, Habib EB, Williams SK, He R, Maliougina M, Park M, Salsman J, Roy S, Braasch I, Roger A, Langelaan D, Dellaire G. PML and PML-like exonucleases restrict retrotransposons in jawed vertebrates. Nucleic Acids Res 2023; 51:3185-3204. [PMID: 36912092 PMCID: PMC10123124 DOI: 10.1093/nar/gkad152] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 02/16/2023] [Accepted: 02/21/2023] [Indexed: 03/14/2023] Open
Abstract
We have uncovered a role for the promyelocytic leukemia (PML) gene and novel PML-like DEDDh exonucleases in the maintenance of genome stability through the restriction of LINE-1 (L1) retrotransposition in jawed vertebrates. Although the mammalian PML protein forms nuclear bodies, we found that the spotted gar PML ortholog and related proteins in fish function as cytoplasmic DEDDh exonucleases. In contrast, PML proteins from amniote species localized both to the cytoplasm and formed nuclear bodies. We also identified the PML-like exon 9 (Plex9) genes in teleost fishes that encode exonucleases. Plex9 proteins resemble TREX1 but are unique from the TREX family and share homology to gar PML. We also characterized the molecular evolution of TREX1 and the first non-mammalian TREX1 homologs in axolotl. In an example of convergent evolution and akin to TREX1, gar PML and zebrafish Plex9 proteins suppressed L1 retrotransposition and could complement TREX1 knockout in mammalian cells. Following export to the cytoplasm, the human PML-I isoform also restricted L1 through its conserved C-terminus by enhancing ORF1p degradation through the ubiquitin-proteasome system. Thus, PML first emerged as a cytoplasmic suppressor of retroelements, and this function is retained in amniotes despite its new role in the assembly of nuclear bodies.
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Affiliation(s)
| | - Kathleen L Vergunst
- Department of Biochemistry & Molecular Biology, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
| | - Elias B Habib
- Department of Pathology, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
| | - Shelby K Williams
- Department of Biochemistry & Molecular Biology, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
| | - Raymond He
- Department of Biochemistry & Molecular Biology, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
| | - Maria Maliougina
- Department of Biochemistry & Molecular Biology, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
| | - Mika Park
- Department of Pathology, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
| | - Jayme Salsman
- Department of Pathology, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
| | - Stéphane Roy
- Department of Stomatology, Faculty of Dentistry, Université de Montréal, Montréal, QB, Canada
| | - Ingo Braasch
- Michigan State University, Department of Integrative Biology and Ecology, Evolution, and Behavior Program, East Lansing, MI, USA
| | - Andrew J Roger
- Department of Biochemistry & Molecular Biology, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
| | - David N Langelaan
- Department of Biochemistry & Molecular Biology, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
| | - Graham Dellaire
- Department of Pathology, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
- Department of Biochemistry & Molecular Biology, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
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5
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Bryan C, Le J, Wei X, Yang K. Saccharomyces cerevisiae apurinic/apyrimidinic endonuclease 1 repairs abasic site-mediated DNA-peptide/protein cross-links. DNA Repair (Amst) 2023; 126:103501. [PMID: 37075541 DOI: 10.1016/j.dnarep.2023.103501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 03/28/2023] [Accepted: 04/04/2023] [Indexed: 04/21/2023]
Abstract
Saccharomyces cerevisiae apurinic/apyrimidinic (AP) endonuclease 1 (yApn1) is a key player of the base excision repair pathway. This multifunctional enzyme is an AP endonuclease, 3'-5' exonuclease, 3'-phosphodiesterase, and participates in nucleotide incision repair. To the best of our knowledge, the known substrates of yApn1 are small DNA lesions such as AP sites and 3'-phospho-α,β-unsaturated aldehyde (3'-PUA). Here, we wish to report in vitro findings that yApn1 repairs bulky DNA-peptide cross-links (DpCs) and DNA-protein cross-links (DPCs) arising from AP sites and 3'-PUA. We chemically synthesized stable and linkage-defined DpCs and DPCs by oxime ligation and reductive amination, respectively. Our steady-state kinetic data showed that yApn1 repairs a 10-mer peptide-conjugated AP site and 3'-PUA with comparable efficiencies to that of processing the unconjugated lesions. We demonstrated that yApn1 is the predominant enzyme that incises AP-DpC in yeast cell extracts. We also demonstrated that yApn1 incises AP-DPCs in a DPC size-dependent manner, and prior DPC proteolysis by trypsin facilitates the repair. We further found that yApn1 removes 3'-PUA-histone DPCs with moderate efficiencies. Together, our results uncovered a novel role of yApn1 in DPC repair, and support the emerging model that proteolysis is required for efficient DPC repair.
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Affiliation(s)
- Cameron Bryan
- Division of Chemical Biology and Medicinal Chemistry, College of Pharmacy, The University of Texas at Austin, Austin, TX 78712, United States
| | - Jennifer Le
- Division of Chemical Biology and Medicinal Chemistry, College of Pharmacy, The University of Texas at Austin, Austin, TX 78712, United States
| | - Xiaoying Wei
- Division of Chemical Biology and Medicinal Chemistry, College of Pharmacy, The University of Texas at Austin, Austin, TX 78712, United States; Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, United States
| | - Kun Yang
- Division of Chemical Biology and Medicinal Chemistry, College of Pharmacy, The University of Texas at Austin, Austin, TX 78712, United States.
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6
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Potential health risks of mRNA-based vaccine therapy: A hypothesis. Med Hypotheses 2023; 171:111015. [PMID: 36718314 PMCID: PMC9876036 DOI: 10.1016/j.mehy.2023.111015] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2022] [Revised: 09/08/2022] [Accepted: 01/24/2023] [Indexed: 01/26/2023]
Abstract
Therapeutic applications of synthetic mRNA were proposed more than 30 years ago, and are currently the basis of one of the vaccine platforms used at a massive scale as part of the public health strategy to get COVID-19 under control. To date, there are no published studies on the biodistribution, cellular uptake, endosomal escape, translation rates, functional half-life and inactivation kinetics of synthetic mRNA, rates and duration of vaccine-induced antigen expression in different cell types. Furthermore, despite the assumption that there is no possibility of genomic integration of therapeutic synthetic mRNA, only one recent study has examined interactions between vaccine mRNA and the genome of transfected cells, and reported that an endogenous retrotransposon, LINE-1 is unsilenced following mRNA entry to the cell, leading to reverse transcription of full length vaccine mRNA sequences, and nuclear entry. This finding should be a major safety concern, given the possibility of synthetic mRNA-driven epigenetic and genomic modifications arising. We propose that in susceptible individuals, cytosolic clearance of nucleotide modified synthetic (nms-mRNAs) is impeded. Sustained presence of nms-mRNA in the cytoplasm deregulates and activates endogenous transposable elements (TEs), causing some of the mRNA copies to be reverse transcribed. The cytosolic accumulation of the nms-mRNA and the reverse transcribed cDNA molecules activates RNA and DNA sensory pathways. Their concurrent activation initiates a synchronized innate response against non-self nucleic acids, prompting type-I interferon and pro-inflammatory cytokine production which, if unregulated, leads to autoinflammatory and autoimmune conditions, while activated TEs increase the risk of insertional mutagenesis of the reverse transcribed molecules, which can disrupt coding regions, enhance the risk of mutations in tumour suppressor genes, and lead to sustained DNA damage. Susceptible individuals would then expectedly have an increased risk of DNA damage, chronic autoinflammation, autoimmunity and cancer. In light of the current mass administration of nms-mRNA vaccines, it is essential and urgent to fully understand the intracellular cascades initiated by cellular uptake of synthetic mRNA and the consequences of these molecular events.
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7
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Okay S. Involvement of retroelements in the autoimmune response in humans. EXPLORATION OF MEDICINE 2022. [DOI: 10.37349/emed.2022.00092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Retroelements are mobile genomic components requiring an RNA intermediate which is reverse-transcribed into complementary DNA for transposition. Human genome contains a vast amount of retroelements including retrotransposons and endogenous retroviruses. These elements are categorized according to presence or absence of long terminal repeats, LTRs or non-LTRs, as well as autonomous and non-autonomous according to involvement of reverse transcriptase. The retroelements have been accumulated in mammalian genomes over all evolutionary times through vertical transmission, and many of them were inactivated through accumulation of mutations. However, the retroelements entered into genome within the last 200,000 years are mostly functional. Some of the active retroelements are associated with varying autoimmune diseases because anti-retroelement antibodies might cross-react with other proteins in the human body. For instance, autoimmunity and inflammation could be stimulated by increased expression of long interspersed element 1 (LINE-1 or L1) or decreased L1 degradation. Different regulation of L1 expression might be related to the genetic and sex-related variations or environmental factors. Activation of retroelements is also controlled by epigenetic silencing mechanisms such as histone modification. Elevated levels of L1 retroelements could trigger the production of type I interferon, a crucial innate defense mechanism in mammals against viruses, and systemic autoimmune response is induced. Loss-of-function in some deoxyribonucleases (DNases) such as three prime repair exonuclease 1 that degrades reverse-transcribed DNA is also related to autoimmune diseases. Additionally, human endogenous retroviruses also play a role in autoimmune diseases. Involvement of retroelements in autoimmune disorders is exemplified with three diseases, i.e. systemic lupus erythematosus, Aicardi–Goutières syndrome, and multiple sclerosis.
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Affiliation(s)
- Sezer Okay
- Department of Vaccine Technology, Vaccine Institute, Hacettepe University, 06210 Ankara, Turkey
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8
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Wang Q, Du J, Hua S, Zhao K. TREX1 Plays Multiple Roles in Human Diseases. Cell Immunol 2022; 375:104527. [DOI: 10.1016/j.cellimm.2022.104527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 03/12/2022] [Accepted: 04/10/2022] [Indexed: 11/15/2022]
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9
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Kim SH, Kim GH, Kemp MG, Choi JH. TREX1 degrades the 3' end of the small DNA oligonucleotide products of nucleotide excision repair in human cells. Nucleic Acids Res 2022; 50:3974-3984. [PMID: 35357486 PMCID: PMC9023299 DOI: 10.1093/nar/gkac214] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 03/02/2022] [Accepted: 03/18/2022] [Indexed: 01/01/2023] Open
Abstract
The nucleotide excision repair (NER) machinery removes UV photoproducts from DNA in the form of small, excised damage-containing DNA oligonucleotides (sedDNAs) ∼30 nt in length. How cells process and degrade these byproducts of DNA repair is not known. Using a small scale RNA interference screen in UV-irradiated human cells, we identified TREX1 as a major regulator of sedDNA abundance. Knockdown of TREX1 increased the level of sedDNAs containing the two major UV photoproducts and their association with the NER proteins TFIIH and RPA. Overexpression of wild-type but not nuclease-inactive TREX1 significantly diminished sedDNA levels, and studies with purified recombinant TREX1 showed that the enzyme efficiently degrades DNA located 3′ of the UV photoproduct in the sedDNA. Knockdown or overexpression of TREX1 did not impact the overall rate of UV photoproduct removal from genomic DNA or cell survival, which indicates that TREX1 function in sedDNA degradation does not impact NER efficiency. Taken together, these results indicate a previously unknown role for TREX1 in promoting the degradation of the sedDNA products of the repair reaction. Because TREX1 mutations and inefficient DNA degradation impact inflammatory and immune signaling pathways, the regulation of sedDNA degradation by TREX1 may contribute to photosensitive skin disorders.
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Affiliation(s)
- Seon Hee Kim
- Biometrology Group, Division of Chemical and Biological Metrology, Korea Research Institute of Standards and Science, Daejeon 305-340, Republic of Korea.,Department of Bio-Analytical Science, University of Science & Technology, Daejeon 305-340, Republic of Korea
| | - Geun Hoe Kim
- Biometrology Group, Division of Chemical and Biological Metrology, Korea Research Institute of Standards and Science, Daejeon 305-340, Republic of Korea.,Department of Bio-Analytical Science, University of Science & Technology, Daejeon 305-340, Republic of Korea
| | - Michael G Kemp
- Department of Pharmacology and Toxicology, Wright State University Boonshoft School of Medicine, Dayton, OH 45435, USA.,Dayton Veterans Administration Medical Center, Dayton, OH 45428, USA
| | - Jun-Hyuk Choi
- Biometrology Group, Division of Chemical and Biological Metrology, Korea Research Institute of Standards and Science, Daejeon 305-340, Republic of Korea.,Department of Bio-Analytical Science, University of Science & Technology, Daejeon 305-340, Republic of Korea
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10
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Abstract
The DNA damage response (DDR) fulfils essential roles to preserve genome integrity. Targeting the DDR in tumors has had remarkable success over the last decade, exemplified by the licensing of PARP inhibitors for cancer therapy. Recent studies suggest that the application of DDR inhibitors impacts on cellular innate and adaptive immune responses, wherein key DNA repair factors have roles in limiting chronic inflammatory signaling. Antitumor immunity plays an emerging part in cancer therapy, and extensive efforts have led to the development of immune checkpoint inhibitors overcoming immune suppressive signals in tumors. Here, we review the current understanding of the molecular mechanisms underlying DNA damage-triggered immune responses, including cytosolic DNA sensing via the cGAS/STING pathway. We highlight the implications of DDR components for therapeutic outcomes of immune checkpoint inhibitors or their use as biomarkers. Finally, we discuss the rationale for novel combinations of DDR inhibitors with antagonists of immune checkpoints and current hindrances limiting their broader therapeutic applications.
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Affiliation(s)
- Domenic Pilger
- Wellcome Trust/Cancer Research UK Gurdon Institute, Department of Biochemistry, University of Cambridge, Cambridge CB2 1QN, United Kingdom
| | - Leonard W Seymour
- Department of Oncology, University of Oxford, Oxford, Oxford OX3 7DQ, United Kingdom
| | - Stephen P Jackson
- Wellcome Trust/Cancer Research UK Gurdon Institute, Department of Biochemistry, University of Cambridge, Cambridge CB2 1QN, United Kingdom
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11
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Santa P, Garreau A, Serpas L, Ferriere A, Blanco P, Soni C, Sisirak V. The Role of Nucleases and Nucleic Acid Editing Enzymes in the Regulation of Self-Nucleic Acid Sensing. Front Immunol 2021; 12:629922. [PMID: 33717156 PMCID: PMC7952454 DOI: 10.3389/fimmu.2021.629922] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 01/21/2021] [Indexed: 12/24/2022] Open
Abstract
Detection of microbial nucleic acids by the innate immune system is mediated by numerous intracellular nucleic acids sensors. Upon the detection of nucleic acids these sensors induce the production of inflammatory cytokines, and thus play a crucial role in the activation of anti-microbial immunity. In addition to microbial genetic material, nucleic acid sensors can also recognize self-nucleic acids exposed extracellularly during turn-over of cells, inefficient efferocytosis, or intracellularly upon mislocalization. Safeguard mechanisms have evolved to dispose of such self-nucleic acids to impede the development of autoinflammatory and autoimmune responses. These safeguard mechanisms involve nucleases that are either specific to DNA (DNases) or RNA (RNases) as well as nucleic acid editing enzymes, whose biochemical properties, expression profiles, functions and mechanisms of action will be detailed in this review. Fully elucidating the role of these enzymes in degrading and/or processing of self-nucleic acids to thwart their immunostimulatory potential is of utmost importance to develop novel therapeutic strategies for patients affected by inflammatory and autoimmune diseases.
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Affiliation(s)
- Pauline Santa
- CNRS-UMR 5164, ImmunoConcEpT, Bordeaux University, Bordeaux, France
| | - Anne Garreau
- CNRS-UMR 5164, ImmunoConcEpT, Bordeaux University, Bordeaux, France
| | - Lee Serpas
- Department of Pathology, New York University Grossman School of Medicine, New York, NY, United States
| | | | - Patrick Blanco
- CNRS-UMR 5164, ImmunoConcEpT, Bordeaux University, Bordeaux, France
- Immunology and Immunogenetic Department, Bordeaux University Hospital, Bordeaux, France
| | - Chetna Soni
- Department of Pathology, New York University Grossman School of Medicine, New York, NY, United States
| | - Vanja Sisirak
- CNRS-UMR 5164, ImmunoConcEpT, Bordeaux University, Bordeaux, France
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12
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Reisländer T, Groelly FJ, Tarsounas M. DNA Damage and Cancer Immunotherapy: A STING in the Tale. Mol Cell 2020; 80:21-28. [PMID: 32810436 DOI: 10.1016/j.molcel.2020.07.026] [Citation(s) in RCA: 162] [Impact Index Per Article: 40.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 07/08/2020] [Accepted: 07/28/2020] [Indexed: 12/19/2022]
Abstract
Cancer immunotherapies enhance anti-tumor immune responses using checkpoint inhibitors, such as PD-1 or PD-L1 inhibitors. Recent studies, however, have extended the scope of immunotherapeutics by unveiling DNA damage-induced innate immunity as a novel target for cancer treatment. Elucidating the interplay among the DNA damage response (DDR), cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway activation, and anti-tumoral immunity is critical for the development of effective cancer immunotherapies. Here, we discuss the current understanding of the mechanisms by which DNA damage activates immune responses that target and eradicate cancer cells. Yet, understanding how cancer cells can escape this immune surveillance and promote tumor progression represents an outstanding challenge. We highlight the most recent clinical advances, in particular how pharmacological fine-tuning of innate/adaptive immunity and its combination with DDR inhibitors, ionizing radiation (IR), and chemotherapy can be exploited to improve cancer treatment.
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Affiliation(s)
- Timo Reisländer
- Department of Oncology, The CR-UK/MRC Oxford Institute for Radiation Oncology, University of Oxford, Oxford OX3 7DQ, UK
| | - Florian J Groelly
- Department of Oncology, The CR-UK/MRC Oxford Institute for Radiation Oncology, University of Oxford, Oxford OX3 7DQ, UK
| | - Madalena Tarsounas
- Department of Oncology, The CR-UK/MRC Oxford Institute for Radiation Oncology, University of Oxford, Oxford OX3 7DQ, UK.
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13
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Ford AL, Chin VW, Fellah S, Binkley MM, Bodin AM, Balasetti V, Taiwo Y, Kang P, Lin D, Jen JC, Grand MG, Bogacki M, Liszewski MK, Hourcade D, Chen Y, Hassenstab J, Lee JM, An H, Miner JJ, Atkinson JP. Lesion evolution and neurodegeneration in RVCL-S: A monogenic microvasculopathy. Neurology 2020; 95:e1918-e1931. [PMID: 32887784 PMCID: PMC7682842 DOI: 10.1212/wnl.0000000000010659] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 04/10/2020] [Indexed: 12/17/2022] Open
Abstract
Objective To characterize lesion evolution and neurodegeneration in retinal vasculopathy with cerebral leukoencephalopathy and systemic manifestations (RVCL-S) using multimodal MRI. Methods We prospectively performed MRI and cognitive testing in RVCL-S and healthy control cohorts. Gray and white matter volume and disruption of white matter microstructure were quantified. Asymmetric spin echo acquisition permitted voxel-wise oxygen extraction fraction (OEF) calculation as an in vivo marker of microvascular ischemia. The RVCL-S cohort was included in a longitudinal analysis of lesion subtypes in which hyperintense lesions on fluid-attenuated inversion recovery (FLAIR), T1-postgadolinium, and diffusion-weighted imaging were delineated and quantified volumetrically. Results Twenty individuals with RVCL-S and 26 controls were enrolled. White matter volume and microstructure declined faster in those with RVCL–S compared to controls. White matter atrophy in RVCL-S was highly linear (ρ = −0.908, p < 0.0001). Normalized OEF was elevated in RVCL-S and increased with disease duration. Multiple cognitive domains, specifically those measuring working memory and processing speed, were impaired in RVCL-S. Lesion volumes, regardless of subtype, progressed/regressed with high variability as a function of age, while FLAIR lesion burden increased near time to death (p < 0.001). Conclusion RVCL-S is a monogenic microvasculopathy affecting predominantly the white matter with regard to atrophy and cognitive impairment. White matter volumes in RVCL-S declined linearly, providing a potential metric against which to test the efficacy of future therapies. Progressive elevation of white matter OEF suggests that microvascular ischemia may underlie neurodegeneration in RVCL-S.
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Affiliation(s)
- Andria L Ford
- From the Department of Neurology (A.L.F., V.W.C., S.F., M.B.M., A.M.B., V.B., Y.T., P.K., Y.C., J.H., J.-M.L.), Mallinckrodt Institute of Radiology (A.L.F., J.-M.L., H.A.), Department of Ophthalmology (M.G.G.), and Department of Medicine (M.B., M.K.L., D.H., J.J.M., J.P.A.), Division of Rheumatology, Washington University School of Medicine, St. Louis, MO; Department of Radiology (D.L.), The Johns Hopkins University School of Medicine, Baltimore, MD; and Department of Neurology (J.C.J.), Icahn School of Medicine at Mount Sinai, New York, NY.
| | - Victoria W Chin
- From the Department of Neurology (A.L.F., V.W.C., S.F., M.B.M., A.M.B., V.B., Y.T., P.K., Y.C., J.H., J.-M.L.), Mallinckrodt Institute of Radiology (A.L.F., J.-M.L., H.A.), Department of Ophthalmology (M.G.G.), and Department of Medicine (M.B., M.K.L., D.H., J.J.M., J.P.A.), Division of Rheumatology, Washington University School of Medicine, St. Louis, MO; Department of Radiology (D.L.), The Johns Hopkins University School of Medicine, Baltimore, MD; and Department of Neurology (J.C.J.), Icahn School of Medicine at Mount Sinai, New York, NY
| | - Slim Fellah
- From the Department of Neurology (A.L.F., V.W.C., S.F., M.B.M., A.M.B., V.B., Y.T., P.K., Y.C., J.H., J.-M.L.), Mallinckrodt Institute of Radiology (A.L.F., J.-M.L., H.A.), Department of Ophthalmology (M.G.G.), and Department of Medicine (M.B., M.K.L., D.H., J.J.M., J.P.A.), Division of Rheumatology, Washington University School of Medicine, St. Louis, MO; Department of Radiology (D.L.), The Johns Hopkins University School of Medicine, Baltimore, MD; and Department of Neurology (J.C.J.), Icahn School of Medicine at Mount Sinai, New York, NY
| | - Michael M Binkley
- From the Department of Neurology (A.L.F., V.W.C., S.F., M.B.M., A.M.B., V.B., Y.T., P.K., Y.C., J.H., J.-M.L.), Mallinckrodt Institute of Radiology (A.L.F., J.-M.L., H.A.), Department of Ophthalmology (M.G.G.), and Department of Medicine (M.B., M.K.L., D.H., J.J.M., J.P.A.), Division of Rheumatology, Washington University School of Medicine, St. Louis, MO; Department of Radiology (D.L.), The Johns Hopkins University School of Medicine, Baltimore, MD; and Department of Neurology (J.C.J.), Icahn School of Medicine at Mount Sinai, New York, NY
| | - Allie M Bodin
- From the Department of Neurology (A.L.F., V.W.C., S.F., M.B.M., A.M.B., V.B., Y.T., P.K., Y.C., J.H., J.-M.L.), Mallinckrodt Institute of Radiology (A.L.F., J.-M.L., H.A.), Department of Ophthalmology (M.G.G.), and Department of Medicine (M.B., M.K.L., D.H., J.J.M., J.P.A.), Division of Rheumatology, Washington University School of Medicine, St. Louis, MO; Department of Radiology (D.L.), The Johns Hopkins University School of Medicine, Baltimore, MD; and Department of Neurology (J.C.J.), Icahn School of Medicine at Mount Sinai, New York, NY
| | - Vamshi Balasetti
- From the Department of Neurology (A.L.F., V.W.C., S.F., M.B.M., A.M.B., V.B., Y.T., P.K., Y.C., J.H., J.-M.L.), Mallinckrodt Institute of Radiology (A.L.F., J.-M.L., H.A.), Department of Ophthalmology (M.G.G.), and Department of Medicine (M.B., M.K.L., D.H., J.J.M., J.P.A.), Division of Rheumatology, Washington University School of Medicine, St. Louis, MO; Department of Radiology (D.L.), The Johns Hopkins University School of Medicine, Baltimore, MD; and Department of Neurology (J.C.J.), Icahn School of Medicine at Mount Sinai, New York, NY
| | - Yewande Taiwo
- From the Department of Neurology (A.L.F., V.W.C., S.F., M.B.M., A.M.B., V.B., Y.T., P.K., Y.C., J.H., J.-M.L.), Mallinckrodt Institute of Radiology (A.L.F., J.-M.L., H.A.), Department of Ophthalmology (M.G.G.), and Department of Medicine (M.B., M.K.L., D.H., J.J.M., J.P.A.), Division of Rheumatology, Washington University School of Medicine, St. Louis, MO; Department of Radiology (D.L.), The Johns Hopkins University School of Medicine, Baltimore, MD; and Department of Neurology (J.C.J.), Icahn School of Medicine at Mount Sinai, New York, NY
| | - Peter Kang
- From the Department of Neurology (A.L.F., V.W.C., S.F., M.B.M., A.M.B., V.B., Y.T., P.K., Y.C., J.H., J.-M.L.), Mallinckrodt Institute of Radiology (A.L.F., J.-M.L., H.A.), Department of Ophthalmology (M.G.G.), and Department of Medicine (M.B., M.K.L., D.H., J.J.M., J.P.A.), Division of Rheumatology, Washington University School of Medicine, St. Louis, MO; Department of Radiology (D.L.), The Johns Hopkins University School of Medicine, Baltimore, MD; and Department of Neurology (J.C.J.), Icahn School of Medicine at Mount Sinai, New York, NY
| | - Doris Lin
- From the Department of Neurology (A.L.F., V.W.C., S.F., M.B.M., A.M.B., V.B., Y.T., P.K., Y.C., J.H., J.-M.L.), Mallinckrodt Institute of Radiology (A.L.F., J.-M.L., H.A.), Department of Ophthalmology (M.G.G.), and Department of Medicine (M.B., M.K.L., D.H., J.J.M., J.P.A.), Division of Rheumatology, Washington University School of Medicine, St. Louis, MO; Department of Radiology (D.L.), The Johns Hopkins University School of Medicine, Baltimore, MD; and Department of Neurology (J.C.J.), Icahn School of Medicine at Mount Sinai, New York, NY
| | - Joanna C Jen
- From the Department of Neurology (A.L.F., V.W.C., S.F., M.B.M., A.M.B., V.B., Y.T., P.K., Y.C., J.H., J.-M.L.), Mallinckrodt Institute of Radiology (A.L.F., J.-M.L., H.A.), Department of Ophthalmology (M.G.G.), and Department of Medicine (M.B., M.K.L., D.H., J.J.M., J.P.A.), Division of Rheumatology, Washington University School of Medicine, St. Louis, MO; Department of Radiology (D.L.), The Johns Hopkins University School of Medicine, Baltimore, MD; and Department of Neurology (J.C.J.), Icahn School of Medicine at Mount Sinai, New York, NY
| | - M Gilbert Grand
- From the Department of Neurology (A.L.F., V.W.C., S.F., M.B.M., A.M.B., V.B., Y.T., P.K., Y.C., J.H., J.-M.L.), Mallinckrodt Institute of Radiology (A.L.F., J.-M.L., H.A.), Department of Ophthalmology (M.G.G.), and Department of Medicine (M.B., M.K.L., D.H., J.J.M., J.P.A.), Division of Rheumatology, Washington University School of Medicine, St. Louis, MO; Department of Radiology (D.L.), The Johns Hopkins University School of Medicine, Baltimore, MD; and Department of Neurology (J.C.J.), Icahn School of Medicine at Mount Sinai, New York, NY
| | - Madonna Bogacki
- From the Department of Neurology (A.L.F., V.W.C., S.F., M.B.M., A.M.B., V.B., Y.T., P.K., Y.C., J.H., J.-M.L.), Mallinckrodt Institute of Radiology (A.L.F., J.-M.L., H.A.), Department of Ophthalmology (M.G.G.), and Department of Medicine (M.B., M.K.L., D.H., J.J.M., J.P.A.), Division of Rheumatology, Washington University School of Medicine, St. Louis, MO; Department of Radiology (D.L.), The Johns Hopkins University School of Medicine, Baltimore, MD; and Department of Neurology (J.C.J.), Icahn School of Medicine at Mount Sinai, New York, NY
| | - M Kathryn Liszewski
- From the Department of Neurology (A.L.F., V.W.C., S.F., M.B.M., A.M.B., V.B., Y.T., P.K., Y.C., J.H., J.-M.L.), Mallinckrodt Institute of Radiology (A.L.F., J.-M.L., H.A.), Department of Ophthalmology (M.G.G.), and Department of Medicine (M.B., M.K.L., D.H., J.J.M., J.P.A.), Division of Rheumatology, Washington University School of Medicine, St. Louis, MO; Department of Radiology (D.L.), The Johns Hopkins University School of Medicine, Baltimore, MD; and Department of Neurology (J.C.J.), Icahn School of Medicine at Mount Sinai, New York, NY
| | - Dennis Hourcade
- From the Department of Neurology (A.L.F., V.W.C., S.F., M.B.M., A.M.B., V.B., Y.T., P.K., Y.C., J.H., J.-M.L.), Mallinckrodt Institute of Radiology (A.L.F., J.-M.L., H.A.), Department of Ophthalmology (M.G.G.), and Department of Medicine (M.B., M.K.L., D.H., J.J.M., J.P.A.), Division of Rheumatology, Washington University School of Medicine, St. Louis, MO; Department of Radiology (D.L.), The Johns Hopkins University School of Medicine, Baltimore, MD; and Department of Neurology (J.C.J.), Icahn School of Medicine at Mount Sinai, New York, NY
| | - Yasheng Chen
- From the Department of Neurology (A.L.F., V.W.C., S.F., M.B.M., A.M.B., V.B., Y.T., P.K., Y.C., J.H., J.-M.L.), Mallinckrodt Institute of Radiology (A.L.F., J.-M.L., H.A.), Department of Ophthalmology (M.G.G.), and Department of Medicine (M.B., M.K.L., D.H., J.J.M., J.P.A.), Division of Rheumatology, Washington University School of Medicine, St. Louis, MO; Department of Radiology (D.L.), The Johns Hopkins University School of Medicine, Baltimore, MD; and Department of Neurology (J.C.J.), Icahn School of Medicine at Mount Sinai, New York, NY
| | - Jason Hassenstab
- From the Department of Neurology (A.L.F., V.W.C., S.F., M.B.M., A.M.B., V.B., Y.T., P.K., Y.C., J.H., J.-M.L.), Mallinckrodt Institute of Radiology (A.L.F., J.-M.L., H.A.), Department of Ophthalmology (M.G.G.), and Department of Medicine (M.B., M.K.L., D.H., J.J.M., J.P.A.), Division of Rheumatology, Washington University School of Medicine, St. Louis, MO; Department of Radiology (D.L.), The Johns Hopkins University School of Medicine, Baltimore, MD; and Department of Neurology (J.C.J.), Icahn School of Medicine at Mount Sinai, New York, NY
| | - Jin-Moo Lee
- From the Department of Neurology (A.L.F., V.W.C., S.F., M.B.M., A.M.B., V.B., Y.T., P.K., Y.C., J.H., J.-M.L.), Mallinckrodt Institute of Radiology (A.L.F., J.-M.L., H.A.), Department of Ophthalmology (M.G.G.), and Department of Medicine (M.B., M.K.L., D.H., J.J.M., J.P.A.), Division of Rheumatology, Washington University School of Medicine, St. Louis, MO; Department of Radiology (D.L.), The Johns Hopkins University School of Medicine, Baltimore, MD; and Department of Neurology (J.C.J.), Icahn School of Medicine at Mount Sinai, New York, NY
| | - Hongyu An
- From the Department of Neurology (A.L.F., V.W.C., S.F., M.B.M., A.M.B., V.B., Y.T., P.K., Y.C., J.H., J.-M.L.), Mallinckrodt Institute of Radiology (A.L.F., J.-M.L., H.A.), Department of Ophthalmology (M.G.G.), and Department of Medicine (M.B., M.K.L., D.H., J.J.M., J.P.A.), Division of Rheumatology, Washington University School of Medicine, St. Louis, MO; Department of Radiology (D.L.), The Johns Hopkins University School of Medicine, Baltimore, MD; and Department of Neurology (J.C.J.), Icahn School of Medicine at Mount Sinai, New York, NY
| | - Jonathan J Miner
- From the Department of Neurology (A.L.F., V.W.C., S.F., M.B.M., A.M.B., V.B., Y.T., P.K., Y.C., J.H., J.-M.L.), Mallinckrodt Institute of Radiology (A.L.F., J.-M.L., H.A.), Department of Ophthalmology (M.G.G.), and Department of Medicine (M.B., M.K.L., D.H., J.J.M., J.P.A.), Division of Rheumatology, Washington University School of Medicine, St. Louis, MO; Department of Radiology (D.L.), The Johns Hopkins University School of Medicine, Baltimore, MD; and Department of Neurology (J.C.J.), Icahn School of Medicine at Mount Sinai, New York, NY
| | - John P Atkinson
- From the Department of Neurology (A.L.F., V.W.C., S.F., M.B.M., A.M.B., V.B., Y.T., P.K., Y.C., J.H., J.-M.L.), Mallinckrodt Institute of Radiology (A.L.F., J.-M.L., H.A.), Department of Ophthalmology (M.G.G.), and Department of Medicine (M.B., M.K.L., D.H., J.J.M., J.P.A.), Division of Rheumatology, Washington University School of Medicine, St. Louis, MO; Department of Radiology (D.L.), The Johns Hopkins University School of Medicine, Baltimore, MD; and Department of Neurology (J.C.J.), Icahn School of Medicine at Mount Sinai, New York, NY
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Tao SS, Wu GC, Zhang Q, Zhang TP, Leng RX, Pan HF, Ye DQ. TREX1 As a Potential Therapeutic Target for Autoimmune and Inflammatory Diseases. Curr Pharm Des 2020; 25:3239-3247. [PMID: 31475890 DOI: 10.2174/1381612825666190902113218] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 08/27/2019] [Indexed: 12/20/2022]
Abstract
BACKGROUND AND OBJECTIVES The 3' repair exonuclease 1 (TREX1) gene is the major DNA-specific 3'-5 'exonuclease of mammalian cells which reduces single- and double-stranded DNA (ssDNA and dsDNA) to prevent undue immune activation mediated by the nucleic acid. TREX1 is also a crucial suppressor of selfrecognition that protects the host from inappropriate autoimmune activations. It has been revealed that TREX1 function is necessary to prevent host DNA accumulating after cell death which could actuate an autoimmune response. In the manuscript, we will discuss in detail the latest advancement to study the role of TREX1 in autoimmune disease. METHODS As a pivotal cytoprotective, antioxidant, anti-apoptotic, immunosuppressive, as well as an antiinflammatory molecule, the functional mechanisms of TREX1 were multifactorial. In this review, we will briefly summarize the latest advancement in studying the role of TREX1 in autoimmune disease, and discuss its potential as a therapeutic target for these diseases. RESULTS Deficiency of TREX1 in human patients and murine models is characterized by systemic inflammation and the disorder of TREX1 functions drives inflammatory responses leading to autoimmune disease. Moreover, much more studies revealed that mutations in TREX1 have been associated with a range of autoimmune disorders. But it is also unclear whether the mutations of TREX1 play a causal role in the disease progression, and whether manipulation of TREX1 has a beneficial effect in the treatment of autoimmune diseases. CONCLUSION Integration of functional TREX1 biology into autoimmune diseases may further deepen our understanding of the development and pathogenesis of autoimmune diseases and provide new clues and evidence for the treatment of autoimmune diseases.
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Affiliation(s)
- Sha-Sha Tao
- Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, 81 Meishan Road, Hefei, Anhui, China
| | - Guo-Cui Wu
- School of Nursing, Anhui Medical University, 15 Feicui Road, Hefei, Anhui, China
| | - Qin Zhang
- Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, 81 Meishan Road, Hefei, Anhui, China
| | - Tian-Ping Zhang
- Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, 81 Meishan Road, Hefei, Anhui, China
| | - Rui-Xue Leng
- Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, 81 Meishan Road, Hefei, Anhui, China
| | - Hai-Feng Pan
- Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, 81 Meishan Road, Hefei, Anhui, China
| | - Dong-Qing Ye
- Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, 81 Meishan Road, Hefei, Anhui, China
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15
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Simpson SR, Hemphill WO, Hudson T, Perrino FW. TREX1 - Apex predator of cytosolic DNA metabolism. DNA Repair (Amst) 2020; 94:102894. [PMID: 32615442 DOI: 10.1016/j.dnarep.2020.102894] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Accepted: 06/03/2020] [Indexed: 12/13/2022]
Abstract
The cytosolic Three prime Repair EXonuclease 1 (TREX1) is a powerful DNA-degrading enzyme required for clearing cytosolic DNA to prevent aberrant inflammation and autoimmunity. In the absence of TREX1 activity, cytosolic DNA pattern recognition receptors of the innate immune system are constitutively activated by undegraded TREX1 substrates. This triggers a chronic inflammatory response in humans expressing mutant TREX1 alleles, eliciting a spectrum of rare autoimmune diseases dependent on the nature of the mutation. The precise origins of cytosolic DNA targeted by TREX1 continue to emerge, but DNA emerging from the nucleus or taken up by the cell could represent potential sources. In this Review, we explore the biochemical and immunological data supporting the role of TREX1 in suppressing cytosolic DNA sensing, and discuss the possibility that TREX1 may contribute to maintenance of genome integrity.
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Affiliation(s)
- Sean R Simpson
- Department of Biochemistry, Center for Structural Biology, Wake Forest School of Medicine, Winston-Salem, NC 27157, United States
| | - Wayne O Hemphill
- Department of Biochemistry, Center for Structural Biology, Wake Forest School of Medicine, Winston-Salem, NC 27157, United States
| | - Teesha Hudson
- Department of Biochemistry, Center for Structural Biology, Wake Forest School of Medicine, Winston-Salem, NC 27157, United States
| | - Fred W Perrino
- Department of Biochemistry, Center for Structural Biology, Wake Forest School of Medicine, Winston-Salem, NC 27157, United States.
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16
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Wiser C, Kim B, Vincent J, Ascano M. Small molecule inhibition of human cGAS reduces total cGAMP output and cytokine expression in cells. Sci Rep 2020; 10:7604. [PMID: 32371942 PMCID: PMC7200739 DOI: 10.1038/s41598-020-64348-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 04/15/2020] [Indexed: 12/14/2022] Open
Abstract
The cGAS-STING pathway is a major mechanism that mammalian cells utilize to detect cytoplasmic dsDNA from incoming viruses, bacteria, or self. CYCLIC GMP-AMP SYNTHASE (cGAS) is the sensor protein that directly binds dsDNAs. cGAS synthesizes cyclic GMP-AMP (cGAMP), which binds to the adaptor STIMULATOR OF INTERFERON GENES (STING), activating an INTERFERON REGULATORY FACTOR 3 (IRF3)-mediated immune response. Constitutive activation can result in interferonopathies such as Aicardi-Goutieres Syndrome (AGS) or other lupus-like autoimmune disorders. While inhibitors targeting mouse or human cGAS have been reported, the identification of a small molecule that targets both homologs of cGAS has been challenging. Here, we show that RU.521 is capable of potently and selectively inhibiting mouse and human cGAS in cell lines and human primary cells. This inhibitory activity requires the presence of cGAS, but it cannot suppress an immune response in cells activated by RNA, Toll-like receptor ligands, cGAMP, or recombinant interferon. Importantly, when RU.521 is applied to cells, the production of dsDNA-induced intracellular cGAMP is suppressed in a dose-dependent manner. Our work validates the use of RU.521 for probing DNA-induced innate immune responses and underscores its potential as an ideal scaffold towards pre-clinical development, given its potency against human and mouse cGAS.
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Affiliation(s)
- Caroline Wiser
- Vanderbilt University School of Medicine, Nashville, TN, 37232-0146, USA
| | - Byungil Kim
- Vanderbilt University School of Medicine, Nashville, TN, 37232-0146, USA
| | - Jessica Vincent
- Vanderbilt University School of Medicine, Nashville, TN, 37232-0146, USA
| | - Manuel Ascano
- Vanderbilt University School of Medicine, Nashville, TN, 37232-0146, USA.
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17
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Skarlis C, Argyriou E, Mavragani CP. Lymphoma in Sjögren’s Syndrome: Predictors and Therapeutic Options. CURRENT TREATMENT OPTIONS IN RHEUMATOLOGY 2020. [DOI: 10.1007/s40674-020-00138-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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18
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TREX1 531C>T Polymorphism is Associated with High Proviral Load Levels in HTLV-1-Infected Persons. Viruses 2019; 12:v12010007. [PMID: 31861565 PMCID: PMC7019804 DOI: 10.3390/v12010007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Revised: 11/26/2019] [Accepted: 11/28/2019] [Indexed: 02/06/2023] Open
Abstract
Human T-lymphotropic virus type 1 (HTLV-1) deregulates the immune system and cell cycle, resulting in loss of immune tolerance and disease, including HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Three prime repair exonuclease 1 (TREX1) maintains innate immune tolerance of the host and host-cell permissiveness to retroviral infections. TREX1 polymorphisms may influence the course of infection and autoimmune manifestations. The influence of TREX1 531C/T polymorphism was investigated in HTLV-1 infection and development of symptoms among 151 persons infected with HTLV-1 (32 HAM/TSP, 19 rheumatologic manifestations, two dermatitis, five more than one diagnosis, two probable HAM/TSP, and 91 asymptomatic individuals) and 100 uninfected persons in the control group. Polymorphism genotyping and proviral load quantification were performed by real-time polymerase chain reaction (PCR) and antinuclear antibodies (ANAs) were screened by an indirect immunofluorescence assay. No statistically significant difference was found in polymorphism genotype and allele frequencies between the infected and control groups. HAM/TSP patients showed higher frequency of TT genotype than asymptomatic persons (p = 0.0339). Proviral load was significantly higher among individuals with CT/TT genotypes and CC genotype carriers had lower proviral load and higher levels of proinflammatory cytokines. ANAs were present only in the HAM/TSP group. TREX1 531C>T polymorphism seems to be associated with TREX-1 regulation and HTLV-1 infection.
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19
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Nezos A, Makri P, Gandolfo S, De Vita S, Voulgarelis M, Crow MK, Mavragani CP. TREX1 variants in Sjogren's syndrome related lymphomagenesis. Cytokine 2019; 132:154781. [PMID: 31326279 DOI: 10.1016/j.cyto.2019.154781] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 06/28/2019] [Accepted: 07/09/2019] [Indexed: 12/28/2022]
Abstract
Genetic variants of the three-prime repair exonuclease 1 (TREX1) -an exonuclease involved in DNA repair and degradation- have been previously found to increase susceptibility to Aicardi Goutieres syndrome, familial chilblain lupus and systemic lupus erythematosus. We aimed to explore whether TREX1 common variants could influence the risk of primary Sjogren's syndrome (SS) and SS-related lymphoma. Three single nucleotide polymorphisms (SNPs) of the TREX1 gene (rs11797, rs3135941 and rs3135945) were evaluated in 229 SS, 89 SS-lymphoma (70 SS-MALT and 19 SS non-MALT) and 240 healthy controls by PCR-based assays. In available 52 peripheral blood and 26 minor salivary gland tissues from our SS cohort, mRNA expression of type I interferon (IFN) related genes and TREX1 was determined by real-time PCR. Significantly decreased prevalence of rs11797 A minor allele was detected in SS patients complicated by non-MALT lymphoma compared to controls (ΟR [95% CI]: 0.4 [0.2-0.9], p-value: 0.02). SS patients carrying the rs11797 AA genotype had increased type I IFN related gene mRNA expression in minor salivary gland tissues. These data support genetically related dampened type I IFN production as an additional mechanism for SS-related lymphomagenesis.
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Affiliation(s)
- Adrianos Nezos
- Department of Physiology, School of Medicine, National University of Athens, Athens, Greece
| | - Panagiota Makri
- Department of Physiology, School of Medicine, National University of Athens, Athens, Greece
| | - Saviana Gandolfo
- Rheumatology Clinic, Department of Medical and Biological Sciences, Azienda Ospedaliero-Universitaria 'S. Maria della Misericordia', Udine, Italy
| | - Salvatore De Vita
- Rheumatology Clinic, Department of Medical and Biological Sciences, Azienda Ospedaliero-Universitaria 'S. Maria della Misericordia', Udine, Italy
| | - Michael Voulgarelis
- Department of Pathophysiology, School of Medicine, National University of Athens, Athens, Greece
| | - Mary K Crow
- Mary Kirkland Center for Lupus Research, Hospital for Special Surgery, Weill Medical College of Cornell University, New York, NY, USA
| | - Clio P Mavragani
- Department of Physiology, School of Medicine, National University of Athens, Athens, Greece; Department of Pathophysiology, School of Medicine, National University of Athens, Athens, Greece; Joint Academic Rheumatology Program, National and Kapodistrian University of Athens, School of Medicine, Athens, Greece.
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20
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Prati B, da Silva Abjaude W, Termini L, Morale M, Herbster S, Longatto-Filho A, Nunes RAL, Córdoba Camacho LC, Rabelo-Santos SH, Zeferino LC, Aguayo F, Boccardo E. Three Prime Repair Exonuclease 1 (TREX1) expression correlates with cervical cancer cells growth in vitro and disease progression in vivo. Sci Rep 2019; 9:351. [PMID: 30674977 PMCID: PMC6344518 DOI: 10.1038/s41598-018-37064-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Accepted: 10/17/2018] [Indexed: 12/17/2022] Open
Abstract
Alterations in specific DNA damage repair mechanisms in the presence of human papillomavirus (HPV) infection have been described in different experimental models. However, the global effect of HPV on the expression of genes involved in these pathways has not been analyzed in detail. In the present study, we compared the expression profile of 135 genes involved in DNA damage repair among primary human keratinocytes (PHK), HPV-positive (SiHa and HeLa) and HPV-negative (C33A) cervical cancer derived cell lines. We identified 9 genes which expression pattern distinguishes HPV-positive tumor cell lines from C33A. Moreover, we observed that Three Prime Repair Exonuclease 1 (TREX1) expression is upregulated exclusively in HPV-transformed cell lines and PHK expressing HPV16 E6 and E7 oncogenes. We demonstrated that TREX1 silencing greatly affects tumor cells clonogenic and anchorage independent growth potential. We showed that this effect is associated with p53 upregulation, accumulation of subG1 cells, and requires the expression of E7 from high-risk HPV types. Finally, we observed an increase in TREX1 levels in precancerous lesions, squamous carcinomas and adenocarcinomas clinical samples. Altogether, our results indicate that TREX1 upregulation is important for cervical tumor cells growth and may contribute with tumor establishment and progression.
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Affiliation(s)
- Bruna Prati
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo (USP), Av. Prof. Lineu Prestes 1374, 05508-900, São Paulo, SP, Brazil
| | - Walason da Silva Abjaude
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo (USP), Av. Prof. Lineu Prestes 1374, 05508-900, São Paulo, SP, Brazil
| | - Lara Termini
- Centro de Investigação Translacional em Oncologia (LIM24), Instituto do Câncer do Estado de São Paulo (ICESP), São Paulo, Brazil
| | - Mirian Morale
- Department of Biochemistry, Institute of Chemistry, USP, São Paulo, Brazil
| | - Suellen Herbster
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo (USP), Av. Prof. Lineu Prestes 1374, 05508-900, São Paulo, SP, Brazil
| | - Adhemar Longatto-Filho
- Laboratory of Medical Investigation (LIM 14), Department of Pathology, School of Medicine, USP, Av. Dr. Arnaldo 455, São Paulo, 01246-903, Brazil.,Life and Health Sciences Research Institute, School of Health Sciences, ICVS/3B's - PT Government Associate Laboratory, University of Minho, Braga, Guimarães, Portugal.,Molecular Oncology Research Center, Barretos Cancer Hospital, Pio XII Foundation, Barretos, Rua Antenor Duarte Villela, 1331, Barretos, 14784-400, Brazil
| | - Rafaella Almeida Lima Nunes
- Centro de Investigação Translacional em Oncologia (LIM24), Instituto do Câncer do Estado de São Paulo (ICESP), São Paulo, Brazil
| | - Lizeth Carolina Córdoba Camacho
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo (USP), Av. Prof. Lineu Prestes 1374, 05508-900, São Paulo, SP, Brazil.,Laboratório de Oncologia Experimental, Departamento de Radiologia, Faculdade de Medicina, USP, São Paulo, SP, Brazil.,Centro de Investigação Translacional em Oncologia, ICESP, São Paulo, SP, Brazil
| | | | - Luiz Carlos Zeferino
- School of Medical Sciences, State University of Campinas (UNICAMP), Rua Alexander Fleming 101, 13083-881, Campinas, SP, Brazil
| | - Francisco Aguayo
- Basic and Clinical Oncology Department, Faculty of Medicine, University of Chile, Santiago, Chile.,Advanced Center for Chronic Diseases (ACCDiS), Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Enrique Boccardo
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo (USP), Av. Prof. Lineu Prestes 1374, 05508-900, São Paulo, SP, Brazil.
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21
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Matz KM, Guzman RM, Goodman AG. The Role of Nucleic Acid Sensing in Controlling Microbial and Autoimmune Disorders. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2018; 345:35-136. [PMID: 30904196 DOI: 10.1016/bs.ircmb.2018.08.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Innate immunity, the first line of defense against invading pathogens, is an ancient form of host defense found in all animals, from sponges to humans. During infection, innate immune receptors recognize conserved molecular patterns, such as microbial surface molecules, metabolites produces during infection, or nucleic acids of the microbe's genome. When initiated, the innate immune response activates a host defense program that leads to the synthesis proteins capable of pathogen killing. In mammals, the induction of cytokines during the innate immune response leads to the recruitment of professional immune cells to the site of infection, leading to an adaptive immune response. While a fully functional innate immune response is crucial for a proper host response and curbing microbial infection, if the innate immune response is dysfunctional and is activated in the absence of infection, autoinflammation and autoimmune disorders can develop. Therefore, it follows that the innate immune response must be tightly controlled to avoid an autoimmune response from host-derived molecules, yet still unencumbered to respond to infection. In this review, we will focus on the innate immune response activated from cytosolic nucleic acids, derived from the microbe or host itself. We will depict how viruses and bacteria activate these nucleic acid sensing pathways and their mechanisms to inhibit the pathways. We will also describe the autoinflammatory and autoimmune disorders that develop when these pathways are hyperactive. Finally, we will discuss gaps in knowledge with regard to innate immune response failure and identify where further research is needed.
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Affiliation(s)
- Keesha M Matz
- School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, WA, United States
| | - R Marena Guzman
- School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, WA, United States
| | - Alan G Goodman
- School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, WA, United States; Paul G. Allen School for Global Animal Health, College of Veterinary Medicine, Washington State University, Pullman, WA, United States.
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22
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Abstract
The innate immune system is the first line of defense against invading pathogens. One important feature of innate immune recognition is self versus nonself discrimination. The selectivity for microbial ligands is achieved through substrate motif specificity, spatial compartmentalization, and functions of negative regulators. Loss-of-function mutations in negative regulators or gain-of-function mutations in drivers of innate immune signaling have been associated with autoimmune diseases such as lupus, rheumatoid arthritis, inflammatory vasculopathy, and a variety of interferonopathies. This review will focus on TREX1 and STING, which are opposing regulators of the cytosolic DNA-sensing pathway. Tremendous effort over the past decade among academic and clinical research groups has elucidated molecular mechanisms underlying immune diseases associated with TREX1 and STING dysfunction. We have also witnessed rapid therapeutic translation of the molecular findings. Several targeted treatment options or druggable candidates are now available for these once incurable diseases. With great enthusiasm from both academia and industry partners, we look forward to seeing the remaining scientific questions answered and, more importantly, the affected patients benefited from these discoveries.
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Affiliation(s)
- Nan Yan
- Department of Immunology, Department of Microbiology, University of Texas Southwestern Medical Center , Dallas, Texas
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23
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Regulation and function of the cGAS-STING pathway of cytosolic DNA sensing. Nat Immunol 2017; 17:1142-9. [PMID: 27648547 DOI: 10.1038/ni.3558] [Citation(s) in RCA: 1256] [Impact Index Per Article: 179.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 08/16/2016] [Indexed: 02/08/2023]
Abstract
The recognition of microbial nucleic acids is a major mechanism by which the immune system detects pathogens. Cyclic GMP-AMP (cGAMP) synthase (cGAS) is a cytosolic DNA sensor that activates innate immune responses through production of the second messenger cGAMP, which activates the adaptor STING. The cGAS-STING pathway not only mediates protective immune defense against infection by a large variety of DNA-containing pathogens but also detects tumor-derived DNA and generates intrinsic antitumor immunity. However, aberrant activation of the cGAS pathway by self DNA can also lead to autoimmune and inflammatory disease. Thus, the cGAS pathway must be properly regulated. Here we review the recent advances in understanding of the cGAS-STING pathway, focusing on the regulatory mechanisms and roles of this pathway in heath and disease.
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24
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Lindahl T. Die intrinsische Fragilität der DNA (Nobel-Aufsatz). Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201602159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Tomas Lindahl
- Cancer Research UK; Clare Hall Laboratories Hertfordshire EN6 3LD UK
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25
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Lindahl T. The Intrinsic Fragility of DNA (Nobel Lecture). Angew Chem Int Ed Engl 2016; 55:8528-34. [PMID: 27220039 DOI: 10.1002/anie.201602159] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Indexed: 11/11/2022]
Abstract
Our cells contain common molecules, such as water or oxygen, that can damage DNA. In his studies Tomas Lindahl has shown how specific repair enzymes remove and replace damaged parts of DNA in a process of vital importance.
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Affiliation(s)
- Tomas Lindahl
- Cancer Research UK, Clare Hall Laboratories, Hertfordshire, EN6 3LD, UK.
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26
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Mavragani IV, Laskaratou DA, Frey B, Candéias SM, Gaipl US, Lumniczky K, Georgakilas AG. Key mechanisms involved in ionizing radiation-induced systemic effects. A current review. Toxicol Res (Camb) 2016; 5:12-33. [PMID: 30090323 PMCID: PMC6061884 DOI: 10.1039/c5tx00222b] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 08/06/2015] [Indexed: 12/11/2022] Open
Abstract
Organisms respond to physical, chemical and biological threats by a potent inflammatory response, aimed at preserving tissue integrity and restoring tissue homeostasis and function. Systemic effects in an organism refer to an effect or phenomenon which originates at a specific point and can spread throughout the body affecting a group of organs or tissues. Ionizing radiation (IR)-induced systemic effects arise usually from a local exposure of an organ or part of the body. This stress induces a variety of responses in the irradiated cells/tissues, initiated by the DNA damage response and DNA repair (DDR/R), apoptosis or immune response, including inflammation. Activation of this IR-response (IRR) system, especially at the organism level, consists of several subsystems and exerts a variety of targeted and non-targeted effects. Based on the above, we believe that in order to understand this complex response system better one should follow a 'holistic' approach including all possible mechanisms and at all organization levels. In this review, we describe the current status of knowledge on the topic, as well as the key molecules and main mechanisms involved in the 'spreading' of the message throughout the body or cells. Last but not least, we discuss the danger-signal mediated systemic immune effects of radiotherapy for the clinical setup.
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Affiliation(s)
- Ifigeneia V Mavragani
- Physics Department , School of Applied Mathematical and Physical Sciences , National Technical University of Athens (NTUA) , Zografou 15780 , Athens , Greece . ; ; Tel: +30-210-7724453
| | - Danae A Laskaratou
- Physics Department , School of Applied Mathematical and Physical Sciences , National Technical University of Athens (NTUA) , Zografou 15780 , Athens , Greece . ; ; Tel: +30-210-7724453
| | - Benjamin Frey
- Department of Radiation Oncology , University Hospital Erlangen , Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) , Erlangen , Germany
| | - Serge M Candéias
- iRTSV-LCBM , CEA , Grenoble F-38000 , France
- IRTSV-LCBM , CNRS , Grenoble F-38000 , France
- iRTSV-LCBM , Univ. Grenoble Alpes , Grenoble F-38000 , France
| | - Udo S Gaipl
- Department of Radiation Oncology , University Hospital Erlangen , Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) , Erlangen , Germany
| | - Katalin Lumniczky
- Frédéric Joliot-Curie National Research Institute for Radiobiology and Radiohygiene , Budapest , Hungary
| | - Alexandros G Georgakilas
- Physics Department , School of Applied Mathematical and Physical Sciences , National Technical University of Athens (NTUA) , Zografou 15780 , Athens , Greece . ; ; Tel: +30-210-7724453
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27
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Abstract
DNA exonucleases, enzymes that hydrolyze phosphodiester bonds in DNA from a free end, play important cellular roles in DNA repair, genetic recombination and mutation avoidance in all organisms. This article reviews the structure, biochemistry, and biological functions of the 17 exonucleases currently identified in the bacterium Escherichia coli. These include the exonucleases associated with DNA polymerases I (polA), II (polB), and III (dnaQ/mutD); Exonucleases I (xonA/sbcB), III (xthA), IV, VII (xseAB), IX (xni/xgdG), and X (exoX); the RecBCD, RecJ, and RecE exonucleases; SbcCD endo/exonucleases; the DNA exonuclease activities of RNase T (rnt) and Endonuclease IV (nfo); and TatD. These enzymes are diverse in terms of substrate specificity and biochemical properties and have specialized biological roles. Most of these enzymes fall into structural families with characteristic sequence motifs, and members of many of these families can be found in all domains of life.
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28
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Hasan M, Fermaintt CS, Gao N, Sakai T, Miyazaki T, Jiang S, Li QZ, Atkinson JP, Morse HC, Lehrman MA, Yan N. Cytosolic Nuclease TREX1 Regulates Oligosaccharyltransferase Activity Independent of Nuclease Activity to Suppress Immune Activation. Immunity 2015; 43:463-74. [PMID: 26320659 DOI: 10.1016/j.immuni.2015.07.022] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Revised: 06/04/2015] [Accepted: 06/19/2015] [Indexed: 01/01/2023]
Abstract
TREX1 is an endoplasmic reticulum (ER)-associated negative regulator of innate immunity. TREX1 mutations are associated with autoimmune and autoinflammatory diseases. Biallelic mutations abrogating DNase activity cause autoimmunity by allowing immunogenic self-DNA to accumulate, but it is unknown how dominant frameshift (fs) mutations that encode DNase-active but mislocalized proteins cause disease. We found that the TREX1 C terminus suppressed immune activation by interacting with the ER oligosaccharyltransferase (OST) complex and stabilizing its catalytic integrity. C-terminal truncation of TREX1 by fs mutations dysregulated the OST complex, leading to free glycan release from dolichol carriers, as well as immune activation and autoantibody production. A connection between OST dysregulation and immune disorders was demonstrated in Trex1(-/-) mice, TREX1-V235fs patient lymphoblasts, and TREX1-V235fs knock-in mice. Inhibiting OST with aclacinomycin corrects the glycan and immune defects associated with Trex1 deficiency or fs mutation. This function of the TREX1 C terminus suggests a potential therapeutic option for TREX1-fs mutant-associated diseases.
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Affiliation(s)
- Maroof Hasan
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Charles S Fermaintt
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Ningguo Gao
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Tomomi Sakai
- Virology and Cellular Immunology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, NIH, Rockville, MD 20852, USA
| | - Takuya Miyazaki
- Virology and Cellular Immunology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, NIH, Rockville, MD 20852, USA
| | - Sixin Jiang
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Quan-Zhen Li
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - John P Atkinson
- Department of Medicine, Division of Rheumatology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Herbert C Morse
- Virology and Cellular Immunology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, NIH, Rockville, MD 20852, USA
| | - Mark A Lehrman
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
| | - Nan Yan
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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29
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Exonuclease TREX1 degrades double-stranded DNA to prevent spontaneous lupus-like inflammatory disease. Proc Natl Acad Sci U S A 2015; 112:5117-22. [PMID: 25848017 DOI: 10.1073/pnas.1423804112] [Citation(s) in RCA: 113] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The TREX1 gene encodes a potent DNA exonuclease, and mutations in TREX1 cause a spectrum of lupus-like autoimmune diseases. Most lupus patients develop autoantibodies to double-stranded DNA (dsDNA), but the source of DNA antigen is unknown. The TREX1 D18N mutation causes a monogenic, cutaneous form of lupus called familial chilblain lupus, and the TREX1 D18N enzyme exhibits dysfunctional dsDNA-degrading activity, providing a link between dsDNA degradation and nucleic acid-mediated autoimmune disease. We determined the structure of the TREX1 D18N protein in complex with dsDNA, revealing how this exonuclease uses a novel DNA-unwinding mechanism to separate the polynucleotide strands for single-stranded DNA (ssDNA) loading into the active site. The TREX1 D18N dsDNA interactions coupled with catalytic deficiency explain how this mutant nuclease prevents dsDNA degradation. We tested the effects of TREX1 D18N in vivo by replacing the TREX1 WT gene in mice with the TREX1 D18N allele. The TREX1 D18N mice exhibit systemic inflammation, lymphoid hyperplasia, vasculitis, and kidney disease. The observed lupus-like inflammatory disease is associated with immune activation, production of autoantibodies to dsDNA, and deposition of immune complexes in the kidney. Thus, dysfunctional dsDNA degradation by TREX1 D18N induces disease in mice that recapitulates many characteristics of human lupus. Failure to clear DNA has long been linked to lupus in humans, and these data point to dsDNA as a key substrate for TREX1 and a major antigen source in mice with dysfunctional TREX1 enzyme.
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30
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Candéias SM, Testard I. The many interactions between the innate immune system and the response to radiation. Cancer Lett 2015; 368:173-8. [PMID: 25681669 DOI: 10.1016/j.canlet.2015.02.007] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2014] [Revised: 02/03/2015] [Accepted: 02/04/2015] [Indexed: 11/15/2022]
Abstract
The role of the immune system in the protection of the organism against biological aggressions is long established and well-studied. A new role emerged more recently in the protection from - and the response to - physical trauma such as exposure to ionizing radiation. A pre-existing inflammation, induced by administration of an inflammatory cytokine or of a Toll-like receptor agonist, is indeed able to mitigate the toxic effects of acute radiation exposure. Conversely, it appears that the innate immune system can be activated during the course of the cellular response to radiation. Activation of different sensors and pattern recognition receptors by intra-cellular molecules such as HMGB1 or DNA released in the extra-cellular milieu or in the cytosol by irradiated cells induces the production of inflammatory and anti-viral cytokines. In addition, in human monocytes and macrophages, the expression of inflammatory cytokine genes can be directly induced by p53- and ATM-dependent mechanisms. This last finding establishes a direct link between radiation-induced DNA damage response and radiation-induced inflammation.
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Affiliation(s)
- Serge M Candéias
- iRTSV-LCBM, CEA, Grenoble F-38000, France; IRTSV-LCBM, CNRS, Grenoble F-38000, France; iRTSV-LCBM, Univ. Grenoble Alpes, Grenoble F-38000, France.
| | - Isabelle Testard
- iRTSV-LCBM, CEA, Grenoble F-38000, France; IRTSV-LCBM, CNRS, Grenoble F-38000, France; iRTSV-LCBM, Univ. Grenoble Alpes, Grenoble F-38000, France
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31
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Ahn J, Ruiz P, Barber GN. Intrinsic self-DNA triggers inflammatory disease dependent on STING. THE JOURNAL OF IMMUNOLOGY 2014; 193:4634-42. [PMID: 25261479 DOI: 10.4049/jimmunol.1401337] [Citation(s) in RCA: 131] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Inflammatory diseases such as Aicardi-Goutières syndrome and severe systemic lupus erythematosus are generally lethal disorders that have been traced to defects in the exonuclease TREX1 (DNase III). Mice lacking TREX1 similarly die at an early age through comparable symptoms, including inflammatory myocarditis, through chronic activation of the stimulator of IFN genes (STING) pathway. In this study, we demonstrate that phagocytes rather than myocytes are predominantly responsible for causing inflammation, an outcome that could be alleviated following adoptive transfer of normal bone marrow into TREX1(-/-) mice. TREX1(-/-) macrophages did not exhibit significant augmented ability to produce proinflammatory cytokines compared with normal macrophages following exposure to STING-dependent activators, but rather appeared chronically stimulated by genomic DNA. These results shed molecular insight into inflammation and provide concepts for the design of new therapies.
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Affiliation(s)
- Jeonghyun Ahn
- Department of Cell Biology, University of Miami Miller School of Medicine, Miami, FL 33136; Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL 33136; and
| | - Phillip Ruiz
- Department of Surgery, University of Miami Miller School of Medicine, Miami, FL 33136
| | - Glen N Barber
- Department of Cell Biology, University of Miami Miller School of Medicine, Miami, FL 33136; Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL 33136; and
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32
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TREX1 C-terminal frameshift mutations in the systemic variant of retinal vasculopathy with cerebral leukodystrophy. Neurol Sci 2014; 36:323-30. [DOI: 10.1007/s10072-014-1944-9] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Accepted: 09/02/2014] [Indexed: 11/25/2022]
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33
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Hasan M, Yan N. Safeguard against DNA sensing: the role of TREX1 in HIV-1 infection and autoimmune diseases. Front Microbiol 2014; 5:193. [PMID: 24817865 PMCID: PMC4012220 DOI: 10.3389/fmicb.2014.00193] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Accepted: 04/11/2014] [Indexed: 12/14/2022] Open
Abstract
Innate immune recognition is crucial for host responses against viral infections, including infection by human immunodeficiency virus 1 (HIV-1). Human cells detect such invading pathogens with a collection of pattern recognition receptors that activate the production of antiviral proteins, such as the cytokine interferon-type I, to initiate antiviral responses immediately as well as the adaptive immune response for long-term protection. To establish infection in the host, many viruses have thus evolved strategies for subversion of these mechanisms of innate immunity. For example, acute infection by HIV-1 and other retroviruses have long been thought to be non-immunogenic, signifying suppression of host defenses by these pathogens. Studies in the past few years have begun to uncover a multifaceted scheme of how HIV-1 evades innate immune detection, especially of its DNA, by exploiting host proteins. This review will discuss the host mechanisms of HIV-1 DNA sensing and viral immune evasion, with a particular focus on TREX1, three prime repair exonuclease 1, a host 3′ exonuclease (also known as DNase III).
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Affiliation(s)
- Maroof Hasan
- Department of Internal Medicine, University of Texas Southwestern Medical Center Dallas, TX, USA ; DDepartment of Microbiology, University of Texas Southwestern Medical Center Dallas, TX, USA
| | - Nan Yan
- Department of Internal Medicine, University of Texas Southwestern Medical Center Dallas, TX, USA ; DDepartment of Microbiology, University of Texas Southwestern Medical Center Dallas, TX, USA
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34
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Lindahl T. My journey to DNA repair. GENOMICS PROTEOMICS & BIOINFORMATICS 2012; 11:2-7. [PMID: 23453014 PMCID: PMC4357663 DOI: 10.1016/j.gpb.2012.12.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Accepted: 12/07/2012] [Indexed: 01/13/2023]
Abstract
I completed my medical studies at the Karolinska Institute in Stockholm but have always been devoted to basic research. My longstanding interest is to understand fundamental DNA repair mechanisms in the fields of cancer therapy, inherited human genetic disorders and ancient DNA. I initially measured DNA decay, including rates of base loss and cytosine deamination. I have discovered several important DNA repair proteins and determined their mechanisms of action. The discovery of uracil-DNA glycosylase defined a new category of repair enzymes with each specialized for different types of DNA damage. The base excision repair pathway was first reconstituted with human proteins in my group. Cell-free analysis for mammalian nucleotide excision repair of DNA was also developed in my laboratory. I found multiple distinct DNA ligases in mammalian cells, and led the first genetic and biochemical work on DNA ligases I, III and IV. I discovered the mammalian exonucleases DNase III (TREX1) and IV (FEN1). Interestingly, expression of TREX1 was altered in some human autoimmune diseases. I also showed that the mutagenic DNA adduct O6-methylguanine (O6mG) is repaired without removing the guanine from DNA, identifying a surprising mechanism by which the methyl group is transferred to a residue in the repair protein itself. A further novel process of DNA repair discovered by my research group is the action of AlkB as an iron-dependent enzyme carrying out oxidative demethylation.
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Affiliation(s)
- Tomas Lindahl
- Cancer Research UK London Research Institute, Clare Hall Laboratories, South Mimms EN6 3LD, United Kingdom.
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35
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Mason PA, Cox LS. The role of DNA exonucleases in protecting genome stability and their impact on ageing. AGE (DORDRECHT, NETHERLANDS) 2012; 34:1317-1340. [PMID: 21948156 PMCID: PMC3528374 DOI: 10.1007/s11357-011-9306-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Accepted: 08/19/2011] [Indexed: 05/30/2023]
Abstract
Exonucleases are key enzymes involved in many aspects of cellular metabolism and maintenance and are essential to genome stability, acting to cleave DNA from free ends. Exonucleases can act as proof-readers during DNA polymerisation in DNA replication, to remove unusual DNA structures that arise from problems with DNA replication fork progression, and they can be directly involved in repairing damaged DNA. Several exonucleases have been recently discovered, with potentially critical roles in genome stability and ageing. Here we discuss how both intrinsic and extrinsic exonuclease activities contribute to the fidelity of DNA polymerases in DNA replication. The action of exonucleases in processing DNA intermediates during normal and aberrant DNA replication is then assessed, as is the importance of exonucleases in repair of double-strand breaks and interstrand crosslinks. Finally we examine how exonucleases are involved in maintenance of mitochondrial genome stability. Throughout the review, we assess how nuclease mutation or loss predisposes to a range of clinical diseases and particularly ageing.
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Affiliation(s)
- Penelope A. Mason
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU UK
| | - Lynne S. Cox
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU UK
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Ostergaard E, Joensen F, Sundberg K, Duno M, Hansen FJ, Batbayli M, Sørensen N, Born AP. A novel RNASEH2B splice site mutation responsible for Aicardi-Goutieres syndrome in the Faroe Islands. Acta Paediatr 2012; 101:e509-13. [PMID: 22882256 DOI: 10.1111/j.1651-2227.2012.02807.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIM The aim of the study was to identify the genetic background for Aicardi-Goutieres syndrome (AGS) in the Faroe Islands. METHODS Four patients with AGS were identified. The patients had a variable phenotype, from a severe prenatal form with intrauterine foetal death to a milder phenotype, albeit still with an early onset, within the first 2-3 months. RESULTS A genome-wide search for homozygosity revealed one single 15.6 Mb region of homozygosity on chromosome 13, which included RNASEH2B, where a splice site mutation c.322-3C>G was identified. Screening of 170 anonymous Faroese controls revealed a carrier frequency of approximately 1.8%, corresponding to an incidence of AGS in the Faroe Islands of around 1 in 12,300. CONCLUSION The previously identified RNASEH2B mutations comprise altogether 20 mutations (missense, nonsense and splice site) with all patients harbouring at least one missense mutation. The severe phenotype of the Faroese patients compared with the previously reported patients with RNASEH2B mutations may be caused by the presence of two null alleles (although some residual normal splicing cannot be ruled out), whereas patients with one or two missense mutations may have some, albeit abnormal, RNASEH2B proteins, and hence some residual activity of RNASEH2B, explaining their milder phenotype.
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Affiliation(s)
- Elsebet Ostergaard
- Department of Clinical Genetics, Copenhagen University Hospital Rigshospitalet, Denmark.
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Abstract
Aicardi-Goutières syndrome (AGS) is a hereditary neurodegenerative disorder characterized mainly by early onset progressive encephalopathy, concomitant with an increase in interferon-α levels in the cerebrospinal fluid. Although it was initially mistaken for intrauterine viral infections, AGS has now been genetically attributed to a lack of adequate processing of cellular nucleic acid debris, which culminates in the perpetual trigger of the innate and acquired immune responses. Although the exact mechanisms governing AGS are not fully understood, significant strides have been recently achieved in better characterizing the disorder and the molecular functions of the five known proteins found mutated in AGS. Studies have now uncovered that AGS is tightly linked with the predisposition to other autoimmune disorders such as familial chilblain lupus and systemic lupus erythematosus. Moreover, at least two of the proteins mutated in AGS, namely TREX1 and SAMHD1, also seem to have antagonistic roles in safeguarding humans from human immunodeficiency virus (HIV) infections. We hereby synthesize the current developments into the greater framework of AGS and suggest that a better understanding of AGS might help usher a better treatment not only for some autoimmune disorders but also possibly for patients suffering from HIV infections, too.
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Affiliation(s)
- C Chahwan
- Department of Molecular Genetics, 1 King's College Circle, University of Toronto, Toronto, Ontario, Canada.
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Beck-Engeser GB, Eilat D, Wabl M. An autoimmune disease prevented by anti-retroviral drugs. Retrovirology 2011; 8:91. [PMID: 22067273 PMCID: PMC3264515 DOI: 10.1186/1742-4690-8-91] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Accepted: 11/08/2011] [Indexed: 11/10/2022] Open
Abstract
Background Both Aicardi-Goutières syndrome, a Mendelian mimic of congenital infection, and the autoimmune disease systemic lupus erythematosus can result from mutations in the gene encoding the enzyme Trex1. In mice, the absence of Trex1 causes severe myocarditis. The enzyme is thought to degrade endogenous retroelements, thus linking them to autoimmune disease. However, inhibition of reverse transcription by the inhibitor zidovudine (AZT) did not ameliorate the disease, weakening the link to retroelements. Findings Here, we show that two other FDA-approved drugs that inhibit reverse transcriptase can ameliorate the myocarditis in Trex1-null mouse. Conclusions The result suggests that retroelements contribute to this hereditary form of autoimmunity, and that treatment with retroelement inhibitors might ameliorate Aicardi-Goutières syndrome in humans.
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Affiliation(s)
- Gabriele B Beck-Engeser
- Department of Microbiology and Immunology, University of California, San Francisco, CA 94143-0414, USA.
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Defects in DNA degradation revealed in crystal structures of TREX1 exonuclease mutations linked to autoimmune disease. DNA Repair (Amst) 2011; 11:65-73. [PMID: 22071149 DOI: 10.1016/j.dnarep.2011.10.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2011] [Revised: 10/07/2011] [Accepted: 10/07/2011] [Indexed: 12/13/2022]
Abstract
Mutations within the human TREX1 3' exonuclease are associated with Aicardi-Goutières Syndrome (AGS) and familial chilblain lupus (FCL). Both AGS and FCL are autoimmune diseases that result in increased levels of interferon alpha and circulating antibodies to DNA. TREX1 is a member of the endoplasmic reticulum (ER)-associated SET complex and participates in granzyme A-mediated cell death to degrade nicked genomic DNA. The loss of TREX1 activity may result in the accumulation of double-stranded DNA (dsDNA) degradation intermediates that trigger autoimmune activation. The X-ray crystal structures of the TREX1 wt apoprotein, the dominant D200H, D200N and D18N homodimer mutants derived from AGS and FCL patients, as well as the recessive V201D homodimer mutant have been determined. The structures of the D200H and D200N mutant proteins reveal the enzyme has lost coordination of one of the active site metals, and the catalytic histidine (H195) is trapped in a conformation pointing away from the active site. The TREX1 D18N and V201D mutants are able to bind both metals in the active site, but with inter-metal distances that are larger than optimal for catalysis. Additionally, all of the mutant structures reveal a reduced mobility in the catalytic histidine, providing further explanation for the loss of catalytic activity. The structures of the mutant TREX1 proteins provide insight into the dysfunction relating to human disease. Additionally, the TREX1 apoprotein structure together with the previously determined wild type substrate and product structures allow us to propose a distinct mechanism for the TREX1 exonuclease.
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HIV-1 restriction factor SAMHD1 is a deoxynucleoside triphosphate triphosphohydrolase. Nature 2011; 480:379-82. [DOI: 10.1038/nature10623] [Citation(s) in RCA: 618] [Impact Index Per Article: 47.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Accepted: 10/11/2011] [Indexed: 12/20/2022]
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Douville RN, Hiscott J. The interface between the innate interferon response and expression of host retroviral restriction factors. Cytokine 2010; 52:108-15. [PMID: 20627758 DOI: 10.1016/j.cyto.2010.04.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2010] [Accepted: 04/23/2010] [Indexed: 01/02/2023]
Abstract
Inhibition of the expression and replication of human retroviruses by different families of host restriction factors has emerged as an important component of antiviral innate immunity. The term "intrinsic immunity" is used to define this specific arm of innate immunity and suggests that host restriction factors are constitutively present within infected cells. The essential role of the interferon (IFN) signaling pathways in eliciting host restriction factor gene transcription - triggered a consequence of pattern recognition receptor signaling - may be an under-recognized aspect of intrinsic immunity. This review discusses the relevance of innate IFN signaling in the induction of retroviral restriction factors, the mechanisms of action of these factors, as well as the counter-regulation of IFN response that results from the plethora of retrovirus-restriction factor interactions.
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Affiliation(s)
- Renée N Douville
- Molecular Oncology Group, Lady Davis Institute for Medical Research, Jewish General Hospital, 3999 Côte Ste-Catherine, Dept. of Microbiology and Medicine, McGill University, Montreal, Quebec, Canada H3T 1E2
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Abstract
In order to maintain genome integrity, it is essential that any DNA damage is repaired. This is achieved in diverse ways in all cells to ensure cellular survival. There is a large repertoire of proteins that remove and repair DNA damage. However, sometimes these processes do not function correctly, leading to genome instability. Studies of DNA repair and genome instability and their causes and cures were showcased in the 2008 Biochemical Society Annual Symposium. The present article provides a summary of the talks given and the subsequent papers in this issue of Biochemical Society Transactions.
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